| DERMONUTRITION | articLe Table 1 Pharmacokinetic parameters of GLA and catechins
AUC0–6 hr (μg mL−1
GLA 300mg in fermented milk matrix) (A)
GLA 300mg consumed alone (B)
hr−1 27.9 ± 9.1a
15.2 ± 10.5 hr
(μmol L−1 AUC0–6
Catechins 47mg in fermented milk matrix
Catechins 47mg consumed alone
hr−1 )
0.248 ± 0.047 0.310 ± 0.026
) Cmax (μg mL−1
12.1 ± 7.03 9.4 ± 5.2
Cmax (μmol L−1 )
0.098 ± 0.015 0.088 ± 0.006
p<0.001 (A) vs b ) Tmax (hr) 2.00 ± 1.00b 4.55 ± 1.29 Tmax (hr)
2.00 ± 1.00 4.50 ± 1.29
Results are mean of 12 volunteers ± SEM with comparison between ingredients consumed alone or mixed in the dairy matrix. a
p<0.01 (B). Adapted from (20)
GLA from borage oil is available in plasma for fermented dairy products. The absorption kinetics was different in the dairy product compared with that in the free oil alone. Indeed, a faster Tmax
and higher AUC were observed. Thus,
the incorporation of the borage oil into the fermented dairy product had a positive effect on its bioavailability. It is postulated that these higher concentrations of GLA can reach the epidermis to exert a greater beneficial effect on the skin when delivered as part of the yogurt matrix compared with the oil alone. To date, the reasons for the enhanced bioavailability are not known, but it could be the result of the emulsification of the ingredients in the product or a direct effect of the probiotics on triglyceride hydrolysis in the gastrointestinal tract. Garaiova et al (19) demonstrated that fatty acid
absorption can be enhanced by preemulsification. In that study, a 45.3% improvement in GLA absorption was observed compared with an 83.6% improvement in the authors’ study. Equally, it was demonstrated that catechins crossed the intestinal barrier and were detected in the plasma. Although the catechins were better absorbed during the early time course of the bioavailability study, the overall absorption profiles during the 6‑hour study were similar, demonstrating that the dairy matrix has no negative effect on catechins absorption. Vitamin E bioavailability was not determined, but previous studies had shown no limitation of absorption when it was ingested from a dairy matrix (not shown). This would suggest that GLA, catechins, and vitamin E could have an effect on skin functioning and as a result, skin studies were initiated.
Skin barrier enhancement efficacy study The authors were interested in the effects of the ingredients on skin barrier function. An open double‑blind randomised clinical study was conducted on 72 free‑living healthy women (n=36 per group) showing no signs of skin diseases, who received twice‑daily doses of 150 mg GLA, 47 mg catechins, and
2 mg vitamin E, mixed in a dairy matrix containing probiotics (L. casei, L. bulgaricus, and S. thermophilus) or the control product (acidified milk without GLA, GTP, vitamin E, and probiotics) for 6 months. The mean age of the 72 women was 29.4 ± 7.9 (range:
20–45 years) and their mean BMI was 22.43 ± 2.8. All had skin phototypes I, II, or III. Volunteers used their usual cleaning and moisturising products throughout the study, but moisturisation was forbidden on the evaluated body areas. TEWL was evaluated on forearm at baseline, 6weeks, 12 weeks, 18 weeks, and 24 weeks. The protocol of this clinical study is described by Puch et al (20). In the intention‑to‑treat (ITT) population (n=72),
the consumption of the dairy product enriched with GLA, GTP, and vitamin E improved skin barrier function as of six weeks and during all the period of consumption of the tested product. Indeed, the effect of the treatment was observed with p= 0.026 with no interaction between treatment and time (p= 0.81). The average improvement of skin barrier function was 13.25% and the highest difference versus control was reached at 18 weeks with 19.3% (improvements of 10.2%, 13%, and 10.2% at 6, 12, and 24 weeks, respectively). The results are presented in Figure 5. As expected, there was deterioration in TEWL over
the winter period (21), which then improved slightly over the rest of the study. However, the consumption of the active dairy product led to an enhancement of the resistance of the skin towards the environment impact by improving skin barrier function. It can be suggested that this resistance was presumably owing to changes in stratum corneum composition. Furthermore,
the
reinforcement of skin barrier function was probably the result of combined synergic effects of GLA, catechins, vitamin E, and probiotics on
the consumption of the active
dairy product led to an enhancement of the resistance of the skin towards the environment impact by improving skin barrier function.
prime-journal.com | May 2011 ❚ 37
Page 1 |
Page 2 |
Page 3 |
Page 4 |
Page 5 |
Page 6 |
Page 7 |
Page 8 |
Page 9 |
Page 10 |
Page 11 |
Page 12 |
Page 13 |
Page 14 |
Page 15 |
Page 16 |
Page 17 |
Page 18 |
Page 19 |
Page 20 |
Page 21 |
Page 22 |
Page 23 |
Page 24 |
Page 25 |
Page 26 |
Page 27 |
Page 28 |
Page 29 |
Page 30 |
Page 31 |
Page 32 |
Page 33 |
Page 34 |
Page 35 |
Page 36 |
Page 37 |
Page 38 |
Page 39 |
Page 40 |
Page 41 |
Page 42 |
Page 43 |
Page 44 |
Page 45 |
Page 46 |
Page 47 |
Page 48 |
Page 49 |
Page 50 |
Page 51 |
Page 52 |
Page 53 |
Page 54 |
Page 55 |
Page 56 |
Page 57 |
Page 58 |
Page 59 |
Page 60 |
Page 61 |
Page 62 |
Page 63 |
Page 64 |
Page 65 |
Page 66 |
Page 67 |
Page 68 |
Page 69 |
Page 70 |
Page 71 |
Page 72 |
Page 73 |
Page 74 |
Page 75 |
Page 76 |
Page 77 |
Page 78 |
Page 79 |
Page 80 |
Page 81 |
Page 82 |
Page 83 |
Page 84